Grinding of toothed wheels, milling-cutters, and the like.



A. AIGHELE. GRINDING 0F TOOTHBD WHEELS, MILLING CUTTERS, AND THE LIKE.

APPLICATION FILED DEG. 15, 1911 00 1L m L 4 n d8 62 m w a P.

Albert flicks/Z6, 6 7%flw Ja s.

liq/thaw? M c JM A. AICHELE. GRINDING OP TOOTHED WHEELS, MILLINGGUTTERS, AND THE LIKE.

PPLIOATION FILED DE(}.15I 1911.

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for the mutual STATES PATENT OFFICE.

AHBERT AICHELE, 0F BADEN, SWITZERLAND.

GRINDING OF TOOTHED-WHZEELS, HILLING-CUTTERS, AND THE LIKE.

Specification of Letters Patent.

Application filed December 15, 1911.

Patented Nov. 1 1, 1913. Serial No. 865,895.

To all whom it may concern:

Be it known that, l, Ansnnr Arcnnnn, a

citizen of the Swiss-Republic, and residing at Baden gwitzerland, haveinvented certain new and useful Improvements in and Relating to theGrinding of Toothed l/Vheels, MillingCutters; and the like, of which thefollowing is a specification.

This invention relates to the mutual grinding of toothed wheels, millingcutters and the like bodies.

It isan'essent-ial condition for the smooth working of toothed wheelsthat the transmission of power shall be perfectly free from jolts, thatis to say, in the case of uniform motion of the driving wheel, the

driven wheel or wheels must also have perfectly uniform motion. Tosatisfy this con dit-ion, it is necessary that the teeth shall have amathematically accurate profile. In practice, however, such constructionis almost im ossible especially in the case of wheels -Wl11C-h arehardened after manufacture. It has heretofore been attempted to grindthe wheels mutually or together after manufacture. A satisfactory resulthas however not been achieved with the processes known hitherto.

The object of the present invention is to provide a process andapparatus for producing the required shape during mutual grinding.

This invention consists in an apparatus rinding of toothed wheels or thelike in which two shafts are provided carrying the wheels to be groundand carrying in addition driving means, suitablerelative movement beingimparted to the wheels to be ground.

Referrin'gto the accompanying drawings which show by way of example oneconstruction of apparatus for carrying into effect the presentinvention, in which the driving of the axles of the toothed wheels iseffected by means of friction disks, Figure 1 is a side elevation. Fig.2 is a sect-ion of the apparatus showing means for angularly displacingthe wheels undergoing grinding relatively to each other. Fig. 3 showsmeans for angularly displacing one of the shafts c and (Z. These twoshafts are driven by friction disks 6 and f which are driven in theirturn by a common friction disk 9 the driving of the disk f beingeffected by the interposition of an idle wheel h for reversing thedirection of rotation ofthe disk I with respect to the disk e.- Thisidle wheel h is pressed by the spring 6 against the disks f an 9. Acrank mechanism 70 is provided by means of which the shaft 0 and throughit the toothed wheel a can be moved to-andfro in the axial direction. IThe screw spindle Z serves the purpose of moving the two axles c and (Znearer to each other until the disks 6 and f come in contact andtherefore the toothed wheels roll on the pitch circles. The arm m ismounted on the center 0 for the purpose of insuring the driving of e bythe disk 9 in every position. I

In order to allow of shifting the position of the toothed wheelsrelatively to their driving device, the wheel 6 for instance is fixed tothe shaft cl by means of an interposed worm drive 72 in such a mannerthat by rotating the worm Wheel relative to the aims can be effected.

According to the above arrangement for the, urpose of startin theprocess the axles of tie two toothed wheels to be ground in, which areat a Variable distance apart, are removed so far apart that at firstthere is no contact between the teeth as in Fig. 4, and then they aregradually moved nearer to each other until the teeth are in contact(Fig. 5), but at first only at the points which constitute the greatestdeviation from the ideal shape of the tooth. At the same time one of thetoothed wheels is moved to-and-fro in. the axial direction by a separatedriving device. This movement is mainly intendedto effect the grindingwith the use of a grinding material. This axial movement is not intendedto accelerate the grinding in, and it affords important advantagesinasmuch as the grinding in of the toothed wheels under the influence ofthe rotary motion does not alone effect the obect in view .111 a per e tmanner because una shifting of the In the form illustrated the two ingportions of the teeth have been ground away in the above describedmanner, the axles of the two toothed wheels are moved nearer to eachother so that fresh places come in contact and are ground away, Fig. 6.

' This is continued until the pitch circles of greater the toothedwheels come in contact with each other.

When the teeth are chosen from the first, thicker than the final shape,then after carrying out the present process the profile of the toothwill have been completely ground, so as to produce toothed wheels whichwill mesh with one another with an ideal shape of tooth. ,If the teethat the commencement of the operations were thicker than the thicknessrequired to enable them to work together without any play when finallyshaped, then at the termination of the operations teeth of ideal formwill be produced which will mesh without play. If the teeth originallywere thinner than required by the ideal form of tooth without play, andcould not therefore be ground down to the said ideal form, a specialapparatus-is provided for the purpose of producing a correct form oftooth with some play between the teeth.

Since in the case of mutually engaging toothed wheels it is usuallyrequired to keep to determined pitch circles, the axles should not bemoved nearer to each other than the point at which the pitch circlestouch each other. Now in order, when this position of the axles has beenreached, to enable the engaging tooth faces of the two wheels to bepressed together with the requisite pressure for mutual grinding, one ofthe toothed wheels to be ground is shifted through a certain angle inthe sense for efiecting this intimate contact, conveniently by rotatingits shaft relatively to the driving means therefor. Thus the grindingoperation; is continued until all parts of the surfaces" of the mutuallycontacting tooth faces have been ground and the ideal tooth form hasbeen produced on one face of the teeth as shown in Fig 7. Whereupon byshifting this toothed wheel in the other sense by the amount of the playbetween the tooth faces the other face of the tooth can be ground.

A one-sided pressure on the teeth acting continuously on one side or theother may also be produced by making the ratio between the peripheralspeeds in the driving device of the two axles of the toothed wheels, orsmaller than the'ratio between the toothed wheels to be ground in, andby this means a grinding away of one side or the other of the toothprofile can be effected.

- friction disks, may

This alteration of the ratio of the pair of driving toothed wheels andthe pair of toothed wheels must naturally be made so small that itseffect will be equal to that of the aforesaid continuous shifting of thewheels to be ground in relatively to the driving device. Non-positivedriving devices, for instance, be employed for driving the axles of thetoothed wheels.

Having now described my invention what I claim as new and desire tosecure by Letters Patent is 1. An apparatus for the mutual grinding oftoothed wheels or the like, comprising axles for the wheels, independentsupports for each axle and means for varying and fixing the distancebetween said axles and arranged to contact with one another, a drivingwheel in contact with one of said friction wheels and an intermediateidle wheel contacting with the other of said friction wheels and saiddrivin wheel toether with means for longitudinally movmg the wheelaxles; as set forth.

2. An apparatus for the mutual grinding of toothed wheels or the like,comprising in combination axles, friction dlsks mounted with the wheelsto be ground on said axles, a friction driving wheel arranged 'incontact with one of said friction disks, a standard for the axle of onefriction disk and for the axle of the driving wheel, a bell crank lever,said lever carrying the other friction disk and being mounted on theaxle of the driving wheel, a screwed rod connecting said standard andsaid lever with hand means for rotating said rod, a further leverpivoted in said standard, a friction disk mounted on said lever and aspring connecting this lever'with the standard; as set forth.

3. An apparatus for the mutual grinding of toothed wheels or the like,comprising pivoted standards with means for determining their distance aart, axles carrying wheels to be groun mounted in said standards, gearwheels mounted on said axles and a driving wheel with axle also mountedin said standards and contacting with one of said gear wheels, a rotarydevice connecting said driving wheel with the other of said wheels andmeans for effecting the longitudinal shifting of the wheel axles; as setforth.

4. An apparatus for the mutual grinding to one another and means fordriving each as set forth.

wheel independently;

the mutual grinding 5. An apparatus for the wheels to be ground withrespect to their in combination two shafts, driving means drivingdevice; as set forth; 10 mounted thereon and intermeshing and com- Intestimon whereof, I aflix my signature prising at least two toothedwheels of such in presence 0 two witnesses.

of toothed wheels or the like comprising 5 relative hardness andrelative diameter that ALBERT AICHELE.

substantially equal degrees of abrasion 00-, F Witnesses: cur per toothon each wheel, together with HARRY A. MCBRIDE, means for changing therelative. posltion of i AUoUsT RIVEGG.

